1. Field of the Invention
The present invention relates generally to optical and optoelectronic system packaging. More specifically, the invention relates to lensed fiber stub assemblies and optical and optoelectronic packages including them.
2. Technical Background
The task of packaging of optical and optoelectronic subsystems into useable system components presents a number of challenges. A functional optical connection must be made from the optical or optoelectronic subsystem to a port on the outside of the package. The port on the outside of the package is desirably adapted to be connected with a standard optical cable, with passive alignment providing a low-loss optical connection between the package and an optical fiber within the cable. Further, for many applications, a hermetically sealed package is required in order to protect the sensitive electronic components from moisture and/or oxygen.
Conventional techniques for packaging optical and optoelectronic subsystems rely on a short length of optical fiber (an optical fiber “stub”) to transport an optical signal from a connected optical cable through a port on the side of the package and into the package interior, and a lens system (typically a spherical lens) to couple (typically by focusing) the light from the fiber stub into the optical or optoelectronic system. However, due to the sizes of the lenses required, the low-throughput assembly process, the need to separately align the fiber stub and lens system with respect to the optical or optoelectronic system, and difficulties in acquiring low cost lenses of suitable tolerance, conventional packaging techniques are difficult to employ in an efficient, cost-effective manufacturing process.